Quick change arbor, hole cutter, and method

ABSTRACT

An arbor is provided for small diameter quick change and standard hole cutters. Each hole cutter defines an outer diameter of less than 1¼ inches, a central aperture and at least one drive pin recess. The arbor comprises an arbor body including an end portion engageable within the central aperture, and a drive member having at least one drive pin for engaging a corresponding drive pin recess of the hole cutter for rotatably driving the hole cutter.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a continuation-in-part of U.S. patent applicationSer. No. 12/050,844, filed Mar. 18, 2008, the contents of which arehereby incorporated by reference in their entirety as part of thepresent disclosure.

FIELD OF THE INVENTION

The present invention relates to arbors for hole cutters, hole cutters,and related methods, and more particularly, to arbors for relativelysmall hole cutters defining outer diameters of less than 1¼ inches andadapted to be driven off of the drive members of corresponding arbors,hole cutters defining outer diameters of less than 1¼ inches, andrelated methods facilitating relatively quick attachment and release ofsuch hole cutters to and from arbors.

BACKGROUND

Prior art hole saws having outer diameters of 1¼ inches or greatertypically include an end portion defining a threaded aperture and atleast two drive pin apertures. The hole saws are coupled to desiredpower tools or machines via arbors, which typically include threaded endportions that engage the saws' threaded apertures, and drive pin plateshaving drive pins that extend into the saws' drive pin apertures. Whenmounting a hole saw of this variety to an arbor, the saw is threadedonto the arbor's end portion until the saw is secured to the arbor bodyand the drive pin apertures align with the corresponding drive pins ofthe arbor's drive pin plate. The drive pin plate is then moved towardthe saw until the drive pins are received within the drive pinapertures. With this arrangement, the hole saw is driven off of thedrive pins as opposed to the arbor's threads, thereby reducing thepossibility that the saw will lock up on the arbor's threads during useor otherwise damage the threads.

Because of their smaller size, conventional hole saws having outerdiameters of less than 1¼ inches (i.e. “small diameter hole saws”) andthe arbors used to drive such small diameter hole saws do not havesufficient room for, and therefore do not include drive pin aperturesand drive pins, respectively. Consequently, typical arbors used to drivesuch smaller diameter hole saws do not include drive pins and, as aresult, typically drive the hole saws with the threaded end portions ofthe arbors. A significant drawback of this configuration is that thehole saw can lock up on the threads during use which, in turn, makes itexceedingly difficult if not impossible to remove the saw from thearbor. When confronted with a hole saw that is locked up on its arbor'sthreads, users may choose to sacrifice the arbor (i.e., dispose of thearbor prematurely with the locked up hole saw attached) to avoid thedifficult and time consuming task of separating the arbor from the holesaw. Further, even if the hole saw is successfully removed from thearbor, the task of removing a locked up hole saw can result in permanentdamage to the arbor and/or hole saw threads.

To assist users in removing locked up small diameter hole saws, priorart hole saws have been devised with wrench flats on the end caps of thehole saws to allow users to employ tools, such as wrenches, to removesuch hole saws when locked up on the threads of an arbor. A typical suchgroup of prior art hole saws is shown in FIG. 14. However, even with theinclusion of wrench flats, the engaging threads of the hole saws and/orarbors can be stripped and/or damaged beyond repair when users attemptto unlock and remove the saws from the arbors. Furthermore, theApplicant is not aware of any teaching or suggestion in the prior art todrive small diameter hole saws off of the wrench flats. And, even if onewere to devise an arbor for driving a small diameter hole saw from thewrench flats (and Applicant is not aware of any such teaching orsuggestion in the prior art), the arbor would not be compatible with allsizes of small diameter hole saws (i.e., the arbor could not drive fromthe flats) because the widths between the wrench flats differ among manydifferent sizes of the small diameter hole saws, typically increasing asthe size of the hole saw increases. In the exemplary group of prior arthole saws shown in FIG. 14, the distance between the wrench flats forthe illustrated hole saws varies as follows:

Prior Art ⅞ inch 15/16 inch 1 inch 1⅙ inch 1⅛ inch Hole Saw DiameterDistance 0.620 inch 0.750 inch 0.745 inch 0.870 inch 0.870 inch BetweenWrench Flats

Three of the most popular sized small diameter hole saws are the ⅞ inchdiameter hole saw, the 1 inch diameter hole saw, and the 1⅛ inchdiameter hole saw. As can be seen, in the exemplary prior art set ofsmall diameter hole saws, each of these most popular hole cuttersdefines a different width or distance between the wrench flats.Accordingly, even if one desired to drive such hole saws from the wrenchflats (which Applicant does not believe is taught or suggested by theprior art), because the wrench flats of such popular sizes definedifferent widths between the flats, the same arbor could not be used todrive the different sized hole saws. Other hole saws in such exemplaryset of prior art small diameter hole saws include an 11/16 inch diameterhole saw, a ¾ inch diameter hole saw, a 25/32 inch diameter hole saw, a13/16 inch diameter hole saw, and a 1 3/16 inch diameter hole saw. Thesehole saws having diameters between 11/16 inch and 13/16 inch definewidths between wrench flats of about 0.620 inch or about 0.625 inch, andthe 1 3/16 inch diameter hole saw defines a width between the wrenchflats of about 0.995 inch.

Another drawback of prior art small diameter hole saws is that, withoutthe aid of drive pins, the arbors can fail to properly secure the sawsduring use, particularly in cases where the hole saws are not correctlythreaded onto the associated arbors. This failure results in off-axiswobble, especially at high rotational speeds. Off-axis wobble can causeundesirable vibrations of the saw during use which, in turn, can reducethe life of the saw and/or create an unacceptable degree of cuttinginaccuracy.

Another drawback of prior art small diameter hole saws is that multiplerevolutions are required to threadedly attach and remove the hole sawsto and from the arbors. Further, when attaching the hole saws, the holesaw threads must be properly aligned and threadedly engaged with thearbor threads to avoid off-axis wobble (as discussed above) and toprevent the arbor threads and/or hole saw threads from stripping, whichcan render the arbor and/or hole saw unusable.

Accordingly, it is an object of the present invention to overcome one ormore of the above-described drawbacks and/or disadvantages of prior artsmall diameter hole saws and arbors.

SUMMARY OF THE INVENTION

In accordance with a first aspect, the present invention is directed toan arbor that is connectable to a hole cutter, and in some embodimentsof the present invention, also is connectable to a standard hole cutter.The hole cutter defines an outer diameter of less than 1¼ inches, an endportion defining an approximately central aperture, and at least onedrive pin recess radially spaced relative to the central aperture. Thearbor comprises an arbor body including on an end thereof a connectingportion engageable with the central aperture of the hole cutter. A drivemember is mounted on the arbor body and includes at least one drive pinradially spaced relative to the arbor body. The drive member is movableaxially relative to the arbor body between engaged and disengagedpositions. In the engaged position, the at least one drive pin isreceived within the respective at least one drive pin recess of the holecutter to rotatably drive the hole cutter with the arbor. In thedisengaged position, the drive member is axially spaced from the holecutter and the drives pin(s) is/are not received within the respectivedrive pin recess(es). In some embodiments of the present invention, theconnecting portion of the arbor body defines a first thread, and thecentral aperture of the hole cutter defines a second thread that isthreadedly engageable with the first thread to connect the hole cutterto the arbor body.

In some embodiments of the present invention, the arbor body and/or holecutter is rotatable relative to the other between a first engagementposition and a second engagement position. In some such embodiments, theangular extent of rotation between the first and second engagementpositions is within the range of about 30° and about 180°, and in somesuch embodiments, the angular extent of rotation is about 90°. In someembodiments of the present invention, the drive member defines anaperture that receives therethrough the arbor body and is configured toallow relative axial movement, but to prevent relative rotationalmovement, of the arbor body and drive member. In some embodiments, thehole cutter comprises two recesses and the drive member comprises twodrive pins receivable within the respective recesses.

In some embodiments of the present invention, the at least one drive pinrecess defines a first substantially flat surface, and the at least onedrive pin defines a second substantially flat surface. The first andsecond substantially flat surfaces engage one another when the drivemember is in the engaged position to further prevent relative rotationalmovement of the hole cutter and drive member.

Some embodiments of the present invention further comprise a biasingmember, such as a coil spring, that normally biases the drive member inthe direction from the disengaged into the engaged position. Preferably,the biasing member automatically drives the drive member into theengaged position upon moving the hole cutter into the second engagementposition. One advantage of this feature is that it facilitatesone-handed attachment of the hole cutter to the arbor, or otherwisefacilitates rapid attachment and detachment of the hole cutter to andfrom the arbor.

In accordance with another aspect of the present invention, the centralaperture of the hole cutter defines a plurality of curvilinearprotrusions and a plurality of relatively recessed curvilinear portionsformed therebetween. The connecting portion of the arbor similarlydefines a plurality of angularly extending protrusions and a pluralityof relatively recessed portions formed therebetween. The arbor and/orhole cutter is rotatable relative to the other between a firstengagement position and a second engagement position. In the firstengagement position, the protrusions of the connecting portion arereceived within the recesses of the central aperture, and theprotrusions of the central aperture are received within the recessedportions of the connecting portion. In the second engagement position,the protrusions of the connecting portion are engaged with theprotrusions of the central aperture. In some such embodiments, theprotrusions of the connecting portion define a first thread, theprotrusions of the central aperture define a second thread, and thefirst and second threads are threadedly engaged with each other in thesecond engagement position. In some such embodiments, the threads on theconnecting portion of the arbor are configured to substantially alignthe at least one drive pin with the at least one drive pin recess of thehole cutter in the second engagement position. In some such embodiments,the first and second threads define an axial clearance therebetweenallowing the end portion of the hole cutter to substantially contact astop surface of the arbor body in the both the first engagement positionand the second engagement position. In some such embodiments, at leastone of the angularly extending protrusions defines a greater or lesserangular extent than at least one other angular extending protrusion ofthe respective central aperture and connecting portion, therebypermitting receipt of the connecting portion within the central aperturein only the first engagement position.

In accordance with another aspect, the present invention is directed toan arbor for a hole cutter defining an outer diameter of less than 1¼inches, an end portion defining an approximately central aperture, andat least one recess radially spaced relative to the central aperture.The arbor comprises first means for drivingly connecting a power tool tothe hole cutter, and second means on an end thereof for releasablyengaging the central aperture of the hole cutter. Third means areprovided for receiving therethrough the first means and for allowingrelative axial movement, but for preventing relative rotationalmovement, of the first means and the third means. The third meansincludes at least one fourth means radially spaced relative to the firstmeans for receipt within the at least one recess of the hole cutter andfor rotatably driving the hole cutter.

In some embodiments, fifth means are provided (i) for allowingrotational movement of at least one of the first means and the holecutter relative to the other between a first engagement position and asecond engagement position for connecting the hole cutter to the firstmeans, and (ii) for substantially aligning the at least one fourth meanswith the at least one corresponding recess of the hole cutter in thesecond engagement position to, in turn, allow axial movement of thethird means relative to the first means in the second engagementposition between a disengaged position axially spaced relative to thehole cutter, and an engaged position with the at least one fourth meansreceived within the corresponding recess of the hole cutter. In someembodiments, sixth means are provided for biasing the third means in thedirection from the disengaged position to the engaged position.

In accordance with another aspect, the present invention is directed toa hole cutter that is attachable to an arbor. The arbor includes athreaded end portion defining at least one male threaded portion, and adrive member including at least one drive pin thereon and movableaxially relative to the arbor between an engaged position with the drivepin engaging the hole cutter, and a disengaged position with the drivepin disengaged from the hole cutter. The hole cutter comprises a bladeincluding a blade body defining an outer diameter of less than 1¼ inchesand a cutting edge defined by a plurality of cutting teeth. An endportion of the hole cutter is fixedly secured to the blade body anddefines an approximately central aperture preferably including on aperipheral portion thereof at least one female threaded portion, and atleast one drive pin recess radially spaced relative to the centralaperture. In some embodiments of the present invention, the femalethreaded portion cooperates with the male threaded portion of the arborto define (i) a first engagement position wherein the lead male andfemale threads engage or substantially engage one another and define afirst axial clearance relative to each other, and (ii) a secondengagement position angularly spaced relative to the first engagementposition. In the second engagement position, the male and female threadsengage one another and define a second axial clearance less than thefirst axial clearance, and the drive pin recess is aligned with arespective drive pin of the arbor for receiving the drive pin with thedrive member located in the engaged position.

Preferably, the arbor further defines a stop surface and, in the secondengagement position, the end portion of the hole cutter is in contactwith the stop surface. In some embodiments, the female threaded portiondefines an axial clearance relative to the male threaded portionallowing the end portion of the hole cutter to substantially contact thestop surface of the arbor in the both the first engagement position andthe second engagement position. In some embodiments, the connectingportion of the arbor defines a plurality of angularly extendingprotrusions and a plurality of relatively recessed portions formedtherebetween; and the central aperture of hole cutter defines aplurality of angularly extending protrusions and a plurality ofrelatively recessed portions formed therebetween. In the firstengagement position, the protrusions of the arbor connecting portion arereceived within the recesses of the central aperture, and theprotrusions of the central aperture are received within the recessedportions of the arbor connecting portion. In the second engagementposition, the protrusions of the arbor connecting portion are engagedwith the protrusions of the central aperture. In some such embodiments,at least one of the angularly extending protrusions defines a greater orlesser angular extent than at least one other angular extendingprotrusion of the respective central aperture and connecting portion,thereby permitting receipt of the connecting portion within the centralaperture in only the first engagement position.

In some embodiments of the present invention, the at least one drive pinrecess defines a first substantially flat surface, and the at least onedrive pin defines a second substantially flat surface that engages thefirst substantially flat surface when the drive member is in the engagedposition. In some such embodiments, the at least one drive pin recessextends axially from a point spaced axially inwardly relative to thecutting edge and through the end portion of the hole cutter.

In accordance with another aspect, the present invention is directed toa hole cutter that is attachable to an arbor. The arbor includes athreaded end portion defining at least one male threaded portion, and adrive member including at least one drive pin thereon and movableaxially relative to the arbor between an engaged position with the drivepin engaging the hole cutter, and a disengaged position with the atleast one drive pin disengaged from the hole cutter. The hole cuttercomprises first means for cutting a hole and defining an outer diameterof less than 1¼ inches, and an approximately central aperture formed inan end portion of the hole cutter for releasably connecting the firstmeans to the arbor. Second means are radially spaced relative to thecentral aperture and are engageable with a respective drive pin of thearbor in the engaged position for rotatably driving the hole saw withthe arbor.

In some embodiments of the present invention, the hole cutter includesat the central aperture third means for engaging the end portion of thearbor in a first engagement position defining a first axial clearancetherebetween, allowing relative rotational movement of at least one ofthe hole cutter and arbor body relative to the other between the firstengagement position and a second engagement position angularly spacedrelative to the first engagement position, and defining a second axialclearance therebetween less than the first axial clearance. In thesecond engagement position, the second means are aligned with the atleast one drive pin of the arbor for receiving the at least one drivepin with the drive member located in the engaged position.

In accordance with another aspect, the present invention is directed toa method comprising the following steps:

(i) providing an arbor including a connecting portion that isconnectable to a hole cutter defining an outer diameter of less than 1¼inches. The hole cutter includes an end portion defining anapproximately central aperture and at least one drive pin recessradially spaced relative to the central aperture. The arbor includes aconnecting portion and a drive member movable axially, but notrotationally, relative to the arbor. The drive member includes at leastone drive pin extending therefrom;

(ii) connecting the central aperture of the hole cutter to theconnecting portion of the arbor;

(iii) inserting the connecting portion of the arbor into the centralaperture of the hole cutter to define a first engagement position;

(iv) substantially aligning the at least one drive pin with the at leastone corresponding drive pin recess of the hole cutter;

(v) either moving or allowing axial movement of the drive memberrelative to the arbor between a disengaged position axially spacedrelative to the hole cutter, and an engaged position with the at leastone drive pin received within the corresponding drive pin recess of thehole cutter; and

(vi) rotatably driving the hole cutter with the at least one drive pinof the arbor.

In some embodiments, the method further comprises the steps of:providing a quick change hole cutter including an approximately centralaperture defining along a periphery thereof a plurality of angularlyextending protrusions and a plurality of recesses formed therebetween;providing an arbor having a connecting portion defining a plurality ofangularly extending protrusions and a plurality of recesses formedtherebetween; inserting at least one of the protrusions of theconnecting portion and the protrusions of the central aperture into therecesses of the other in the first engagement position; and rotating atleast one of the hole cutter and arbor body relative to the other fromthe first engagement position to the second engagement position and, inturn, engaging at least one of the protrusions of the connecting portionand of the central aperture with the other.

Some embodiments of the present invention further comprise the steps ofnormally biasing the drive member from the disengaged position towardthe engaged position and, upon moving the hole cutter from the firstengagement position into the second engagement position, automaticallybiasing the drive pin member into the engaged position to, in turn,drive the at least one drive pin into the corresponding drive pin recessand secure the hole cutter to the arbor.

In accordance with another aspect, the present invention is directed toa plurality of hole cutters, each hole cutter comprises a bladeincluding a blade body defining a respective outer diameter of less than1¼ inches and a cutting edge defined by a plurality of cutting teeth. Abase portion of each hole cutter opposite the cutting edge defines athreaded aperture adapted for threadedly engaging a correspondingthreaded end portion of an arbor. The base portion includes at least twodrive surfaces radially spaced relative to the threaded aperture onsubstantially opposite sides of the threaded aperture relative to eachother and defining a distance therebetween. The plurality of holecutters includes two hole cutters having blade bodies defining differentouter diameters relative to each other that are each one of about ⅞inch, about 1 inch and about 1⅛ inches, and the distance between thedrive surfaces is substantially the same for each of the plurality ofhole cutters.

In some embodiments of the present invention, the plurality of holecutters includes three hole cutters, wherein one hole cutter includes ablade body defining an outer diameter of about ⅞ inch, another holecutter includes a blade body defining an outer diameter of about 1 inch,and another hole cutter includes a blade body defining an outer diameterof about 1⅛ inches. In some embodiments of the present invention, theplurality of hole cutters includes a plurality of hole cutters havingblade bodies defining additional outer diameters, wherein the additionalouter diameters are selected from the group including: about 9/16 inch,about ⅝ inch, about 11/16 inch, about ¾ inch, about 25/32 inch, about13/16 inch, about 15/16 inch, about 1 1/16 inches, and about 1 3/16inches. In some embodiments of the present invention, the outer diameterof the blade body of each hole cutter of the plurality of hole cuttersis different than the outer diameter of the blade body of every otherhole cutter in the plurality of hole cutters.

In accordance with another aspect, the present invention is directed toa plurality of hole cutters. Each hole cutter is attachable to an arborincluding a threaded end portion, and at least two drive membersradially spaced relative to the threaded end portion and movableaxially, but not rotationally, relative to the threaded end portionbetween (i) an engaged position with the drive members engaging arespective hole cutter to rotatably drive the hole cutter, and (ii) adisengaged position with the drive members disengaged from the holecutter. Each hole cutter comprises a blade including a blade bodydefining a respective outer diameter of less than 1¼ inches and acutting edge defined by a plurality of cutting teeth. A base portion ofeach hole cutter located opposite the cutting edge defines a threadedaperture adapted for threadedly engaging the threaded end portion of thearbor. The base portion further includes at least two drive surfacesradially spaced relative to the threaded aperture on substantiallyopposite sides of the threaded aperture relative to each other anddefining a distance therebetween. Each drive surface engages arespective drive member of the arbor in the engaged position forrotatably driving the hole cutter. The plurality of hole cuttersincludes two hole cutters having blade bodies defining different outerdiameters relative to each other that are each one of about ⅞ inch,about 1 inch and about 1⅛ inches, and the distance between the drivesurfaces is substantially the same for each of the plurality of holecutters.

In some embodiments of the present invention, the plurality of holecutters includes three hole cutters, wherein one hole cutter includes ablade body defining an outer diameter of about ⅞ inch, another holecutter includes a blade body defining an outer diameter of about 1 inch,and another hole cutter includes a blade body defining an outer diameterof about 1⅛ inches. Some embodiments of the present invention furthercomprise a plurality of hole cutters having blade bodies definingadditional outer diameters selected from the group including: about 9/16inch, about ⅝ inch, about 11/16 inch, about ¾ inch, about 25/32 inch,about 13/16 inch, about 15/16 inch, about 1 1/16 inches, and about 13/16 inches.

In accordance with another aspect, the present invention is directed toa plurality of hole cutters. Each hole cutter is attachable to an arborincluding a threaded end portion, and at least two drive membersradially spaced relative to the threaded end portion and movableaxially, but not rotationally, relative to the threaded end portionbetween (i) an engaged position with the drive members engaging arespective hole cutter to rotatably drive the hole cutter, and (ii) adisengaged position with the drive members disengaged from the holecutter. Each hole cutter comprises first means for cutting a hole anddefining an outer diameter of less than 1¼ inches; second means forthreadedly connecting the first means to the threaded end portion of thearbor; and a pair of third means radially spaced on opposite sides ofthe second means relative to each other, and defining a distancetherebetween, for engaging respective drive members of the arbor in theengaged position, and for rotatably driving the hole cutter with thearbor. The plurality of hole cutters includes two hole cutters havingfirst means defining different outer diameters relative to each other,and each outer diameter is one of about ⅞ inch, about 1 inch, and about1⅛ inches, and the distance between the third means is substantially thesame for each of the plurality of hole cutters.

In some embodiments of the present invention, the first means is a holecutter blade defining the respective outer diameter, the second means isa threaded aperture, and each third means is a drive surface located onan opposite side of the threaded aperture relative to the other drivesurface.

One advantage of the present invention is that allows a hole saw havingan outer diameter of less than 1¼ inches to be driven off of drive pinsas opposed to the arbor threads to prevent the saw from locking up onthe arbor threads during use. Another advantage of some currentlypreferred embodiments of the present invention is that it allows a holecutter to be relatively quickly engaged with, and disengaged from, thearbor. Yet another advantage of some currently preferred embodiments ofthe present invention is that one arbor can accept both quick change andstandard hole cutters.

Another advantage of the present invention is that it allows all sizesof small diameter hole cutters included in a given set or plurality tobe driven off of the drive pins of the same arbor.

Other objects, advantages and features of the present invention, and/orof the currently preferred embodiments thereof, will become more readilyapparent in view of the following detailed description of the currentlypreferred embodiments and accompanying drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a perspective view of an arbor for a small diameter holecutter according to an embodiment of the invention.

FIG. 2 is an exploded perspective view of the arbor of FIG. 1.

FIG. 3 is a side elevational view of the arbor of FIG. 1.

FIG. 4 is a cross-sectional view of the arbor of FIG. 1.

FIG. 5 is a perspective view of the arbor of FIG. 1 with the hole cutterremoved.

FIG. 6 is a top plan view of the arbor of FIG. 5.

FIG. 7 is a side elevational view of the arbor body of the arbor of FIG.1.

FIG. 8 is a front elevational view of the arbor body of FIG. 7.

FIG. 9 is a perspective view of the drive member of the arbor of FIG. 1.

FIG. 10 is a bottom plan view of the drive member of FIG. 9.

FIG. 11 is a top plan view of the end portion of an embodiment of asmall diameter hole cutter of the present invention.

FIG. 12A is a side elevational view of the arbor of FIG. 1 showing thehole cutter in alignment with the end portion of the arbor body andready for attachment thereon.

FIG. 12B s a side perspective view of the arbor of FIG. 12A showing thehole cutter and arbor body in the first engagement position.

FIG. 12C is a side perspective view of the arbor of FIG. 12B showing thehole cutter and arbor body between the first and second engagementpositions.

FIG. 12D is a side elevational view the arbor of FIG. 12C showing thehole cutter and arbor body fully engaged in the second engagementposition.

FIG. 13 is a somewhat schematic illustration of a standard hole cutterthread form shown in solid lines, and a custom hole cutter thread formin accordance with the currently preferred embodiments of the presentinvention shown in broken lines.

FIG. 14 is a side perspective view of a plurality of prior art smalldiameter hole cutters including wrench flats.

FIG. 15 is a side perspective view of a plurality of small diameter holecutters according to the present invention.

FIG. 16 is a bottom elevational view of the hole cutters shown in FIG.15.

DETAILED DESCRIPTION OF THE CURRENTLY PREFERRED EMBODIMENTS

In FIGS. 1 through 9, an arbor embodying the present invention isindicated generally by the reference numeral 10. The arbor 10 is usablewith small diameter hole cutters. Such small diameter hole cuttersconform to the ASME B94.54-1999 standard, and in accordance with suchASME standard, have an outside diameter of less than 1¼ inches. The term“hole cutter” is used herein to mean any of numerous different types ofcutting tools for cutting holes in work pieces, such as hole saws, sheetmetal hole cutters, etc.; the term “small diameter hole cutter” is usedherein to refer to such hole cutters including blades having outsidediameters of less than 1¼ inches; and the term “arbor” is used herein tomean any of numerous different types of devices for supporting arotating tool, such as a hole cutter, on a power tool such as a drill,and further includes, without limitation, mandrels.

As shown, for example, in FIGS. 2 and 11, a typical small diameter quickchange hole cutter 11 includes a blade body 12 including a cutting edge13 at one end, and an end portion or end plate 14 at the other endopposite the cutting edge. The hole cutter 11 defines at least one drivepin recess 15. The term “recess” is used herein to mean any indentation,recessed surface, aperture, pocket, alcove, concavity, receding portionor space, or any other such feature that is capable of receiving thereinand/or engaging a corresponding protuberance, such as a drive pin, forrotatably driving the hole cutter. In the illustrated embodiment, thehole cutter 11 defines two drive pin recesses 15, each extending axiallyfrom a point spaced axially inwardly from the cutting edge 13 through(and including) the end portion 14. In some such embodiments, therecesses 15 define a first substantially flat surface 16 for engaging acorresponding flat surface 36 of a respective drive pin 34 (described infurther detail below). In some such embodiments, the hole cutter 11defines two diametrically opposed recesses 15; however, as may berecognized by those of ordinary skill in the pertinent art base on theteachings herein, the hole cutter 11 can take any of numerous differentconfigurations and can include any number of recesses 15 that can takeany of numerous different configurations that are engageable withcorresponding drive pins 34 of any form. The cutting edge 13 of the holesaw 11 defines a plurality of cutting teeth (not shown) for cutting ahole in a work piece by rotatably driving the arbor 10 and hole cutter11 and moving the rotatably-driven cutting teeth into the work piece.The end portion 14 defines an approximately central aperture 17extending therethrough. As described further below, in the quick changehole cutter, the central aperture 17 defines a plurality of raisedthreaded portions 18 that are angularly spaced relative to each otherfor threadedly engaging a connecting end portion 22 of the arbor 10, anda plurality of recessed unthreaded portions 19 located between thethreaded portions.

In a conventional or standard small diameter hole cutter or saw (i.e. ahole cutter or saw having an outside diameter of less then 1¼ inches),the central aperture in the end portion of the hole cutter defines acontinuous or substantially continuous thread extending about thecircumference of the aperture. Such standard hole cutters conform to theASME B94.54-1999 standard, and in accordance therewith, define astandard ½-20 UNF-2B thread. Accordingly, the term “standard” or“conventional” hole cutter is used herein to mean a hole cutter that hassuch a threaded aperture; whereas the term “quick change” hole cutter isused herein to mean a hole cutter that does not include such aconventional threaded aperture, but rather includes a connectingaperture defining one or more features to facilitate a quick changeattachment of the hole cutter to the arbor, such as the plural raisedengagement portions and plural recessed portions located therebetweenand described further below.

As shown best in FIGS. 2, 7 and 8, the arbor 10 comprises anaxially-elongated arbor body 20 defining an axially extending pilot bitaperture 26 for receiving a pilot bit 27 (FIG. 13). Although a standardpilot bit is shown in the illustrated embodiment (i.e. a pilot bit thatdoes not include a feature for allowing attachment of the bit to anarbor without tools), it should be noted that the arbor 10 can beconfigured to accept a quick change pilot bit (i.e. a pilot bit thatincludes a feature for allowing attachment of the bit to an arborwithout tools). The arbor body 20 includes a body portion 21 defining astop surface or shoulder 22, and an end portion 23 that extends axiallyfrom the stop surface 22. As described further below, the end portion 23of the arbor is engageable within the central aperture 17 (FIG. 4) ofthe hole cutter 11 to secure the arbor body 20 to the hole cutter. Inthe illustrated embodiments, and as described further below, the endportion 23 threadedly engages the central aperture 17 of the hole saw;however, as may be recognized by those of ordinary skill in thepertinent art based on the teachings herein, any of numerous otherconnection mechanisms or features that are currently known, or thatlater become known, equally may be employed. As can be seen in FIG. 8,the body portion 21 of the arbor defines a “double D” cross-sectionalconfiguration (i.e., a pair of opposing substantially flat side surfaceswith a pair of opposing substantially curvilinear side surfacesextending therebetween); however, as may be recognized by those ofordinary skill in the pertinent art based on the teachings herein, thisconfiguration is only exemplary, and numerous other shapes and/orconfigurations that are currently known, or that later become knownequally may be used. A drive shank 28 is formed on the arbor body 20opposite the end portion 23. In the illustrated embodiment, the driveshank 28 is a quick-release power drive shank of a type known to thoseof ordinary skill in the pertinent art. However, as may be recognized bythose of ordinary skill in the pertinent art based on the teachingsherein, the shank 28 may take the form of any of numerous differenttypes of shanks or other structures that are currently known, or thatlater become known for performing the function of the shank 28.

As shown typically in FIGS. 1-6 and 9-10, the arbor 10 further includesa drive member 30 defining an aperture 32 extending therethrough. Theaperture 32 is configured for receiving the arbor body 20 and engagingthe body portion 21 of the arbor body such that the drive member 30 isprevented from rotating relative to the arbor body 20, but is allowed tomove axially over the arbor body between a first or engaged positionengaging the hole cutter 11 (FIG. 1), and a second or disengagedposition disengaged from the hole cutter 11 (FIG. 12A). As best shown inFIG. 10, the aperture 32 defines a “double D” configuration to matinglyengage the body portion 21 of the arbor body 20; however, as may berecognized by those of ordinary skill in the pertinent art based on theteachings herein, this configuration is only exemplary, and numerousother shapes and/or configurations that are currently known, or thatlater become known equally may be used. The drive member 30 furtherincludes a first surface or bearing surface 31, and at least one drivepin 34 extending axially therefrom. The term “drive pin” is used hereinto mean any protuberance for engaging a corresponding recess on a holecutter and rotatably driving the hole cutter. As may be recognized bythose of ordinary skill in the pertinent art base on the teachingsherein, the at least one drive pin 34 can take any of numerous differentshapes and/or configurations that are currently known, or that laterbecome known. For example, the drive pins can take on cylindrical,circular, or other curvilinear shapes, or rectangular, square, or otherrectilinear shapes, or combinations of any such shapes, and can includesurface features to facilitate engaging and/or driving the hole cutters,such as flats or protrusions that engage corresponding recessed surfaces(or vice versa). In the illustrated embodiment, the drive pins 34 definea substantially rectangular cross-sectional shape, extend axially fromthe first surface 31, are diametrically opposed, and are radially spacedrelative to the aperture 32. Each drive pin 34 is received within acorresponding drive pin recess 15 of the hole cutter 11 when the drivemember 30 is in the engaged as shown in FIGS. 1, 3 and 12D, and isdisplaced from its respective recess 15 when the drive member is in adisengaged position as shown in FIGS. 12A-C. In some embodiments, eachdrive pin 34 defines a second substantially flat surface 36 that opposesand engages the first substantially flat surface 16 of the correspondingdrive pin recesses 15 in the hole cutter 11 when the drive member 30 isin the engaged position to substantially prevent any relative rotationalmovement or play between the drive pins and hole cutter. In theillustrated embodiment, the drive member 30 includes two diametricallyopposed drive pins 34; however, as may be recognized by those ofordinary skill in the pertinent art base on the teachings herein, thedrive member 30 can take any of numerous different configurations andcan include any number of drive pins 34 for rotatably driving the holecutter.

As shown in FIG. 2, a biasing member 40, which in the illustratedembodiment is a coil spring, biases the drive member 30 in the directionfrom the disengaged position toward the engaged position. As describedin further detail below, the biasing member 40 normally biases the drivemember 30 into the engaged position when the drive pins 34 andcorresponding drive pin recesses 15 are placed in alignment and supportthe hole cutter 11 in a manner that substantially prevents off-axiswobble and undesirable vibrations during use. One advantage of thisfeature is that it facilitates one-handed attachment of the hole cutter11 to the arbor 10, or otherwise facilitates rapid attachment anddetachment of the hole cutter to and from the arbor. As describedfurther below, in the currently preferred embodiments of the presentinvention, the drive member 30 abuts or substantially abuts the endportion 14 of the hole cutter 11.

In the illustrated embodiments of the present invention, the arbor 10 isadapted to receive and mount both quick change hole cutters and standardhole cutters. However, the invention and aspects thereof may be embodiedin arbors adapted to mount only quick change hole cutters. In a standardsmall diameter hole cutter (not shown), the threaded aperture in the endplate of the hole cutter (defining a ½-20 UNF-2B thread in accordancewith the above-mentioned ASME standard) threadedly engages the endportion 23 of the arbor body 20 to secure the arbor body thereto. In thequick change hole cutter 11, on the other hand, and as shown typicallyin FIG. 10, the central aperture 17 in the end portion 14 defines aplurality of curvilinear protrusions 18 angularly spaced relative toeach other along the circumference of the aperture, and a plurality ofcurvilinear recesses 19 located therebetween. The curvilinearprotrusions 18 define female threads that threadedly engagecorresponding male threads formed on the end portion 23 of the arborbody 20. More specifically, and as shown in FIGS. 7 and 8, the endportion 23 of the arbor body 20 defines a plurality of angularlyextending, curvilinear arbor protrusions 24 that project radiallyoutwardly, and are angularly spaced relative to each other about thecircumference of the end portion 23, and a plurality of angularlyextending recesses or flats 25 located therebetween. In the illustratedembodiment, one or more of the protrusions 24 on the arbor body 20 andthe corresponding protrusions 18 on the hole cutter 11 defines a greateror lesser angular extent than the other protrusions so that the quickchange hole cutter can be fitted to the end portion 23 of the arbor bodyin only one first engagement position, and in that first engagementposition, the lead male and female threads can properly engage whenmoving from the first engagement position to the second engagementposition. Similarly, the end portion 14 of the hole cutter 11 of FIG. 10includes a first recess 19 defining a greater angular extent than theopposite second recess 19. Accordingly, in the first engagementposition, the first recess 19 receives the first protrusion 24, thesecond recess 19 receives the second protrusion 24, and this is the onlyposition in which the end portion 23 of the arbor can be received withinthe central aperture 17 of the hole cutter 11. In this first engagementposition, the lead threads of the respective protrusions of the arbor 10and hole cutter 11 engage upon moving at least one of the hole cutter 11and arbor body 20 relative to the other between the first and the secondengagement positions. Because of the different angular extents of theopposing threaded protrusions of the central aperture 17 of the cutter11 and the end portion 23 of the arbor body 20, the end portion 23 canbe received into the central aperture 17 in only one position, and inthat position, the lead male and female threads can engage upon movingthe hole cutter and/or arbor body relative to the other between thefirst and second engagement positions. If desired, or alternatively, thehole cutter and/or arbor can include visual markings thereon that can bealigned or otherwise used to orient the position of the central aperture17 of the hole cutter relative to the connecting portion of the arbor inorder to ensure attachment of the hole to the arbor in the firstengagement position.

As shown in FIGS. 12A through 12D, in order to attach the hole cutter 11to the arbor body 20, the protrusions 24 on the end portion 23 of thearbor body 20 are aligned with the correspondingly-sized recesses 19 ofthe central aperture 17 of the hole cutter. Then, the hole cutter 11 isslipped over the end portion 23 of the arbor body 20 (or vice versa)until the end portion 14 of the hole cutter is adjacent to,substantially in contact with, or in contact with the shoulder (or stopsurface) 22 of the arbor body 20 to thereby place the hole cutter andarbor body in the first engagement position. As indicated above, in thisposition, the lead male threads of the arbor body and lead femalethreads of the hole cutter can engage upon rotating at least onerelative to the other. Then, the hole cutter 11 is rotated relative tothe arbor body 20 from the first engagement position to a secondengagement position (or the arbor body is rotated relative to the holecutter, or both the hole cutter and arbor body are rotated in oppositedirections) to, in turn, threadedly engage the male threaded protrusions24 of the end portion 23 of the arbor body with the corresponding femalethreaded protrusions 18 of the hole cutter, and thereby fixedly securethe hole cutter to the arbor body.

In the illustrated embodiment, the male threads of the arbor bodyprotrusions 24 and the female threads of the hole cutter protrusions 18are configured (or “clocked”) so that when the hole cutter and/or arborbody is rotated from the first engagement position to the secondengagement position, the drive pins 34 of the drive member 30 andrecesses 15 of the hole cutter are substantially aligned in the secondengagement position. This, in turn, allows the drive pins 34 to beaxially received within the corresponding drive pin recesses 15. In onesuch embodiment, the respective first and second substantially flatsurfaces 16 and 36 also engage to further secure the hole cutter to thearbor and prevent rotational movement of the hole cutter relative to thedrive member 30. In a preferred embodiment, the male and female threadsof the protrusions 24 and 18, respectively, are configured so that whenthe hole cutter 11 and/or the arbor body 20 are rotated into the secondengagement position, the end portion 14 of the hole cutter is in contactwith, or substantially in contact with the shoulder 28 of the arbor bodyto, in turn, allow the shoulder 28 to engage and further support thehole cutter during use. In the illustrated embodiments of the presentinvention, there is sufficient axial clearance between the male andfemale threads of the protrusions 24 and 18, respectively, to allow theend portion 14 of the hole cutter 11 to contact or substantially contactthe shoulder 28 of the arbor body 20 in the first engagement position,and to allow the end portion 14 of the hole cutter to remain in contactor substantial contact with the shoulder 28 during rotation between thefirst and second engagement positions, so that in the second engagementposition, the end portion 14 is in contact with, or in substantialcontact with the shoulder 22 of the arbor body 20. During rotationbetween the first and second engagement positions, the threads tend todrive the hole cutter 11 axially inwardly toward the shoulder 22 (orvice versa) and thus substantially eliminate or eliminate the axialclearance between threads in the second engagement position.

As indicated above, one advantage of the currently preferred embodimentsof the present invention is that the threaded end portion 23 of thearbor is threadedly engageable with either (i) quick change holecutters, or (ii) standard hole cutters, as described above. Thecombination of threaded protrusions 24 on the end portion 23 of thearbor body 20 forms an interrupted, but continuous thread pattern forengaging the female threads on a standard hole cutter having a diameterless than 1¼ inches as defined above (i.e., a ½-20 UNF-2B thread). Thus,in order to attach a standard hole cutter to the arbor body, thethreaded aperture in the standard hole cutter cap is fitted over thethreaded end portion 23 of the arbor body, and at least one of the holecutter and arbor body is rotated relative to the other to engage thethreads. Then, the hole cutter and/or arbor is rotated relative to theother to further engage the threads and, in turn, axially move the endportion 14 of the hole cutter into engagement with the shoulder 28 ofthe arbor body. However, unlike quick change hole cutters, when astandard hole cutter is threadedly attached to the arbor, the drivemember 30 will remain in a downward disengaged position and the topsurfaces 38 of the respective drive pins will contact, but not engage,the end portion of the standard hole cutter.

In the currently preferred embodiments of the present invention, therelative rotation of the hole cutter 11 and/or arbor 10 between thefirst and second engagement positions is within the range of about 10degrees and about 180 degrees, is preferably within the range of about30 degrees and about 120 degrees, and is most preferably within therange of about 40 degrees and about 100 degrees. In the illustratedembodiment, the relative rotation between the first and secondengagement positions is about 90 degrees. However, as may be recognizedby those of ordinary skill in the pertinent art based on the teachingsherein, these angular ranges and angles are only exemplary, and numerousother angles and/or angular ranges equally may be employed.

As shown typically in FIG. 13, the arbors and hole cutters of thecurrently preferred embodiments of the present invention define customthread forms that allow the end portions of the arbors to be threadedlyengaged to both quick change hole cutters and standard hole cutters;that allow the quick change hole cutters to engage or substantiallyengage the shoulder of the arbor in both the first and second engagementpositions; and that are timed so that in the second engagement positionthe drive pins of the arbor are aligned or substantially aligned withthe drive pin recesses of the hole cutter. As indicated above, standardhole cutters having hole saw diameters of less than 1¼ inches define a½-20 UNF-2B thread. Accordingly, the custom thread form of the currentlypreferred embodiment of the present invention is based on this standardthread form to allow attachment of the arbor to hole cutters with suchstandard threads; however, the custom thread form also varies from thestandard thread form in order to allow attachment of quick change holecutters as described. The currently preferred small diameter hole cutterembodiments of the present invention define a “½-20 custom thread”. Eachcustom thread defines a thread height “H”, pitch “P”, and included angleas does the respective standard thread form, but defines a differentaxial clearance “a”, root “R”, and crest “C”. In the illustratedembodiments, the customer thread form differs from the standard threadform as follows:

TABLE 1 Different Features Standard Thread Forms Custom Thread FormsRoot (“R”)  0.25 P  0.25 P + a Crest (“C”) 0.125 P 0.125 P − a AxialClearance Not Specified, But a Negligible or Approximately Zero

The minimum clearance “a” for each custom thread form is preferablydetermined in accordance with the following formula:a=((1/pitch)/360))*D, where D equals the degree of rotation between thefirst and second engagement positions. For example, as indicated in thetable below, if the hole cutter includes two threaded protrusions 18 (or“lobes”), it will rotate 90° between the first and second engagementpositions; if the hole cutter includes 3 lobes, it will rotate 60°between the first and second engagement positions; if the hole cutterincludes 4 lobes, it will rotate 45° between the first and secondengagement positions, etc. The minimum axial clearance “a” is set totime the threads so that in the second engagement position the drivepins are aligned or substantially aligned with the respective drive pinrecesses in the hole cutter to allow the drive pins to be moved into theengaged position. The following table lists exemplary minimumapproximate clearances “a” for the ½-20 custom thread forms:

TABLE 2 Minimum Number of Approximate Lobes (or Angular RotationClearance “a” for curvilinear Between First And ½-20 Custom threadedSecond Engagement Thread Form protrusions) Positions (inches) 2 lobe 90°0.012 (square/ rectangle) 3 lobe 60° 0.008 (triangle) 4 lobe 45° 0.006(cross) 5 lobe (pent) 36° 0.005 6 lobe (hex) 30° 0.004

As may be recognized by those of ordinary skill in the pertinent artbased on the teachings herein, these minimum clearances are onlyexemplary, and numerous other clearances equally may be employed.Preferably, the minimum clearance “a” is approximately as defined above;however, if desired, the clearance may be greater than the minimum asdefined above. In some embodiments of the present invention, theclearance is within the range of about 1 to about 1½a. If, for example,the clearance is greater than the respective minimum clearance “a”, thedrive pins will be allowed to move into the drive pins recesses when thehole cutter is located in the second engagement position. If, on theother hand, the clearance is too small such that the hole cutter cannotmove into the second engagement position and thus cannot move the drivepin recesses into alignment with the drive pins, the hole cutter cannotbe properly attached to the arbor.

As shown typically in FIGS. 4, 9 and 10, the drive member 30 defines aperipheral, axially-extending side wall 35 and a bore 37 (FIG. 4) formedon the inner side of the side wall 35. The inner bore 37 of the drivemember 30 and the body portion 21 of the arbor body 20 define anannular, axially-extending compartment 39 for receiving and supportingtherein the first biasing member 40 which, in the illustratedembodiment, is a coil spring. As shown best in FIGS. 2 and 4, the arbor10 includes a retaining clip or ring 44 connectable to a groove 46formed in the body portion 21 of the arbor body 20, a bushing 42 thatengages on its end surface the clip 44, and slidably engages on itsouter surface the bore 37 of the drive member 30 to guide the axialmovement of the drive member 30 between the engaged (FIGS. 2 and 12D)and disengaged (FIG. 12A) positions. As can be seen, the first biasingmember 40 is axially fitted between the bushing 42 and the inner end ofthe drive member 30 to normally bias the drive member outwardly into theengaged position. As described further below, a user can manually engagethe drive member 30 to retract the drive member against the bias of thefirst biasing member 40 into the disengaged position and can, in turn,release the drive member to allow the first biasing member to drive thedrive member from the disengaged to an engaged position. Alternatively,for one-handed attachment, a user can press the end portion 14 of thehole cutter against the drive member 30 to, in turn, correspondinglycompress the coil spring 40 and place the hole cutter against theshoulder 28 of the arbor in the first engagement position. Then, uponrotating the hole cutter with the same hand from the first engagementposition into the second engagement position, the coil springautomatically drives the drive member 30 into the engaged position withthe drive pins 34 received within the corresponding drive pin recesses15 of the hole cutter to complete attachment of the hole cutter to thearbor.

Having thus described the arbor 10 and its components, attention willnow be drawn to a method of attaching and removing hole cutters to andfrom the arbor, respectively. With the drive shank 28 of the arbor 10inserted and engaged by the chuck of a driving tool, such as a drill(not shown) or, prior to insertion and engagement with the tool, the enduser aligns the central aperture 17 of the hole cutter 11 with the endportion 23 of the arbor. If a small diameter quick change hole cutter isused, the hole cutter recesses 18 are aligned with the arbor bodyprotrusions 24 as shown, for example, in FIG. 12A. Once in alignment,the hole cutter is fitted onto the end portion 23 of the arbor body 20such that the arbor body protrusions 24 are received within thecorresponding hole cutter recesses 18, and the end portion or base 14 ofthe hole cutter 14 rests on or about the stop surface or shoulder 28 ofthe arbor body 20. During this step, the user substantiallysimultaneously moves the drive member 30 from the first (engaged)position to the second (disengaged) position and compresses the firstbiasing member 40. At this point the hole saw and arbor are in the firstengagement position as shown in FIG. 12B. Referring to FIGS. 12B through12D, the hole cutter 11 is then rotated from the first engagementposition (FIG. 12B) to the second engagement position (FIG. 12D) suchthat the hole cutter protrusions 19 threadedly engage the respectivearbor body protrusions 24 and, in turn, releasably connect the holecutter 11 to the arbor body 20. When the hole cutter and arbor body arein the second engagement position, the drive pin recesses 15 of the holecutter are substantially aligned with the respective drive pins 34 ofthe drive member 30, thereby allowing the first biasing member 40 toautomatically drive the drive member 30 from the second position (FIG.12A) to the first position (FIG. 12D) and, in turn, drive the drive pins34 into the corresponding recesses 15 in the hole saw. In theillustrated embodiment, with the drive pins 34 fully received into thecorresponding drive pin recesses 15, the first and second substantiallyflat drive pin surfaces engage to further prevent movement of the holecutter 11 relative to the drive member 30 such that the hole cutter 11is fully engaged and attached to the arbor as shown, for example, inFIG. 1.

If a standard small diameter hole cutter (not shown) is used, the enduser aligns the central aperture of the cutter with the end portion 23of the arbor body 20 fitting the hole cutter thereupon, such that thecentral aperture threadedly engages the threads on the arbor protrusions24. Like the quick change hole cutter, the standard hole cutter is thenrotated to threadedly attach the hole cutter to the end portion of thearbor to connect the hole saw to the arbor. However, as noted above, thedrive member 30 will remain in the downward disengaged position and thetop surfaces 38 of the respective drive pins will contact, but notengage, the end portion of the standard cutter. Depending on the threadform, the standard hole cutter may or may not fully engage the shoulderor stop surface 38 of the arbor body 20 when attached to the arbor.

To attach a standard or quick change pilot bit, the bit is inserted intoa pilot bit aperture 26 defined in the arbor body 20. The drive member30 is then moved by at least one of: (i) grasping and physically movingthe drive member 30, and (ii) pressing downward on the drive member 30through engagement with the hole cutter 11 during the step of fittingthe hole cutter onto the end portion of the arbor body, to align afastener aperture 52 in the drive member 30 with a correspondingfastener aperture 54 in the arbor body 20. The fastener aperture in thearbor body 52 is threaded to engage a threaded fastener 56. The fastener56 is then rotated to, in turn, move from a first position disengagedform the pilot bit to a second position engaged with the pilot bit (FIG.4) to thereby prevent axial movement and rotation of the pilot bit (forexample, pilot bit 27) relative to the arbor body 20. As may berecognized by those of ordinary skill in the pertinent art based on theteachings herein, the order in which the pilot bit is inserted and thedrive member is moved is inconsequential; hence, the drive member may bemoved to align the apertures 52, 54 either before or after the pilot bitis inserted. Additionally, if desired, the arbor can be used with thehole cutter only (no pilot bit) or with the pilot bit only (no holecutter).

Referring now to FIGS. 15-16, a plurality of small diameter hole cuttersaccording to another embodiment of the present invention is indicatedgenerally by the reference numeral 100. The illustrated hole cutters canbe driven by an arbor, such as the arbor 10 described above, and aresubstantially similar to the hole cutter 11 described above, andtherefore like reference numerals preceded by the numerals “1”, “2”,“3”, “4”, “5” or “6”, respectively, are used to indicate like elements.The primary difference of the hole cutters 111, 211, 311, 411, 511 and611 in comparison to hole cutter 11 is that the hole cutters 111, 211,311, 411, 511 and 611 define a pair opposing drive surfaces, which inthe illustrated embodiment are substantially flat surfaces, 166, 266,366, 466, 566 and 666, respectively, defining a constant distance orwidth (w) therebetween as described in further detail below. As shown inFIGS. 15-16, each hole cutter 111, 211, 311, 411, 511, 611 includes ablade body 112, 212, 312, 412, 512, 612, respectively, defining an outerdiameter including a cutting edge 113, 213, 313, 413, 513, 613,respectively, defined by a plurality of cutting teeth 129, 229, 329,429, 529, 629, respectively, and a base portion 167, 267, 367, 467, 567,667, respectively, at the other end opposite the cutting edge. The baseportion defines a base surface or end portion 114, 214, 314, 414, 514,614, respectively, that may engage the corresponding stop surface 22 ofthe arbor 10, and an approximately central threaded aperture 117, 217,317, 417, 517, 617, respectively, adapted for threadedly engaging thecorresponding threaded end portion 23 of the arbor 10 to secure therespective hole cutter to the arbor. In the illustrated embodiments, theblade bodies define outer diameters of about ⅞ inch, about 15/16 inch,about 1 inch, about 1 1/16 inches, about 1⅛ inches and about 1 3/16inches, respectively. However, it should be noted that the sizes shownare by way of example only and, therefore, the invention covers allsizes of small diameter hole cutters that are currently know or thatlater become known, having an outside diameter of less than 1¼ inches.For example, the plurality of hole cutters may include withoutlimitation additional hole cutters having blade bodies defining outerdiameters of about 9/16 inch, about ⅝ inch, about 11/16 inch, about ¾inch, about 25/32 inch, and about 13/16 inch.

As previously indicated, the base portion 167, 267, 367, 467, 567, 667of each cutter 111, 211, 311, 411, 511, 611, respectively, furtherdefines at least two opposing drive surfaces 166, 266, 366, 466, 566,666, respectively, that are radially spaced relative to the respectivecentral aperture 117, 217, 317, 417, 517 or 617. The substantially flatsurfaces of the illustrated embodiment are designed for engagingcorresponding drive members or pins of an arbor, such as the pins 38 ofthe arbor 10 described above. Also, as previously indicated, the width(w) between the opposing drive surfaces is substantially the same foreach of the hole cutters shown, and is also substantially the same forall small diameter hole cutter sizes not shown that are included in thegiven plurality or set of hole cutters. One advantage of thisarrangement is that each hole cutter in the plurality of hole cutterscan be driven off of the same arbor. The distance or width (w) ispreferably within the range of about ¼ inch to about 1 inch, and morepreferably is within the range of about ⅜ inch to about ¾ inch. In theillustrated embodiment, the distance or width (w) is about ⅝ inch. Alsoin the illustrated embodiment, the opposing drive surfaces arediametrically opposed; however, it should be noted that the drivesurfaces could be circumferentially or otherwise spaced at otherlocations along the perimeter of the base portion, so long as thedistance between the central points of the surfaces or otherwise betweenthe drive surfaces is substantially the same for every hole cutter sizein the given plurality or set of hole cutters. It should also be notedthat the end portions of the hole cutters 111, 211, 311, 411, 511, 611could define additional pairs of drive surfaces, such as additionalpairs of substantially diametrically opposed and/or substantially flatsurfaces, so long as the distance or width (w) between the additionalpairs of surfaces is substantially the same for every hole cutter sizein a given plurality of hole cutters to allow for use of the same arborto drive the plurality of hole cutters.

Having thus described the hole cutters 111, 211, 311, 411, 511, 611 andarbor 10, attention will now be drawn to a method of attaching andremoving the hole cutters to and from the arbor, respectively. With thedrive shank 28 of the arbor 10 inserted and engaged by the chuck of adriving tool, such as a drill (not shown) or, prior to insertion andengagement with the tool, the end user aligns the central aperture 117,217, 317, 417, 517, 617 of the respective hole cutter with the endportion 23 of the arbor body, fitting the hole cutter thereupon, suchthat the central aperture threadedly engages the threads on the endportion of the arbor 10. Substantially simultaneously, the end usergrasps the drive member 30 to maintain the drive member in thedisengaged position. The hole cutter is then rotated to threadedlyattach the hole cutter to the end portion of the arbor to connect thehole cutter to the arbor. When the hole cutter is completely threaded(or approximately completely threaded) upon the end portion of thearbor, and the drive surfaces 166, 266, 366, 466, 566, 666 of therespective hole cutter are aligned with the substantially flat surfaces36 of the drive pins 34 (or other drive members of a different style orconfigured arbor), the end user releases the drive member 30 so that thedrive member 30 moves into the engaged position so that the drive pins34 engage the respective hole cutter. Alternatively, the drive member isnot spring biased, the user can manually grasp and move the drive memberaxially from the disengaged into the engaged position. In this manner,all hole cutters 111, 211, 311, 411, 511, 611 may be driven by the drivepins or drive members of the arbor, and not the threaded end portion ofthe arbor, thereby preventing the hole cutters from locking up on thearbor threads. It should be noted that although the hole cuttersillustrated in FIGS. 15-16 define a conventionally threaded centralaperture as defined above, this should not be construed as a limitingfactor, as the hole cutters may employ quick change features forattaching and removing the hole cutters in the manner previouslydescribed.

If desired, the arbors, hole cutters and methods disclosed herein,and/or aspects or features of the arbors, hole cutters and methodsdisclosed herein, maybe substantially similar to those disclosed in thefollowing co-pending patent application that is assigned to the Assigneeof the present invention, and is hereby expressly incorporated byreference as part of the present disclosure: U.S. patent applicationSer. No. 12/043,740, filed Mar. 6, 2008, entitled: “Quick Change Arbor,Hole Cutter, and Method”.

As may be recognized by those of ordinary skill in the pertinent artbased on the teachings herein, numerous changes and modifications may bemade to the above-described and other embodiments of the presentinvention without departing from the scope of the invention as definedin the appended claims. For example, the components of the arbor maytake on any of numerous different configurations, or may be formed ofany of numerous different materials, that are currently known, or thatlater become known; any of a variety of the disclosed components may beeliminated, or additional components or features may be added; and thearbors may be used with any of numerous different types of tools thatare currently known, or that later become known. For example, the drivepins may take any of numerous different configurations including, forexample, circular and/or rectangular drive pins that engagecorresponding drive pin recesses and/or apertures in the hole cutter.Similarly, the recesses in the hole cutter can take any of numerousdifferent configurations for receiving or otherwise engaging any ofnumerous different types of drive pins or drive members, such as thesubstantially flat recessed drive surfaces illustrated, curvilineardrive surfaces, or any of numerous other drive surface shapes orconfigurations that are currently known, or that later become known. Thedrive member likewise can take any of numerous different configurations,including, for example, a plate form, a circular, non-circular or othershaped drive member or housing that is movable relative to the arborbody and includes one or more drive pins. The threads on the arborconnecting portion and/or on the central aperture of the hole cutter cantake any of numerous different configurations that are currently known,or that later become known. Alternatively, the connecting portion and/orcentral aperture of the hole cutter may define a structure other thanthreads for engaging the hole cutter to the arbor upon moving the arborand/or hole cutter relative to the other between the first and secondengagement positions. Accordingly, this detailed description of thecurrently-preferred embodiments is to be taken in an illustrative, asopposed to a limiting sense.

1. A plurality of hole cutters, each hole cutter comprising: a bladeincluding a blade body defining a respective outer diameter of less than1¼ inches and a cutting edge defined by a plurality of cutting teeth;and a base portion opposite the cutting edge and defining a threadedaperture adapted for threadedly engaging a corresponding threaded endportion of an arbor, and at least two drive surfaces radially spacedrelative to the threaded aperture on substantially opposite sides of thethreaded aperture relative to each other and defining a distancetherebetween; wherein (i) the plurality of hole cutters includes atleast two hole cutters having blade bodies defining different outerdiameters relative to each other that are selected from the groupconsisting of: about ⅞ inch, about 1 inch, and about 1⅛ inches, and (ii)the distance between the drive surfaces is substantially the same foreach of the plurality of hole cutters.
 2. A plurality of hole cutters asdefined in claim 1, wherein the plurality of hole cutters includes threehole cutters, one hole cutter including a blade body defining an outerdiameter of about ⅞ inch, another hole cutter including a blade bodydefining an outer diameter of about 1 inch, and another hole cutterincluding a blade body defining an outer diameter of about 1⅛ inches. 3.A plurality of hole cutters as defined in claim 2, further comprising aplurality of additional hole cutters having blade bodies definingadditional different outer diameters different relative to each otherselected from the group consisting of: about 9/16 inch, about ⅝ inch,about 11/16 inch, about ¾ inch, about 25/32 inch, about 13/16 inch,about 15/16 inch, about 1 1/16 inches, and about 1 3/16 inches.
 4. Aplurality of hole cutters as defined in claim 3, wherein the outerdiameter of the blade body of each hole cutter of the plurality of holecutters is different than the outer diameter of the blade body of everyother hole cutter in the plurality of hole cutters.
 5. A plurality ofhole cutters as defined in claim 1, wherein the distance between thedrive surfaces is within the range of about ⅜ inch to about ¾ inch.
 6. Aplurality of hole cutters as defined in claim 5, wherein the distancebetween the drive surfaces is about ⅝ inch.
 7. A plurality of holecutters as defined in claim 1, wherein the two drive surfaces arelocated on diametrically opposite sides of the threaded aperturerelative to each other.
 8. A plurality of hole cutters as defined inclaim 1, wherein each drive surface is recessed relative to a peripheralsurface of the hole cutter.
 9. A plurality of hole cutters as defined inclaim 8, wherein each drive surface is substantially flat.
 10. Aplurality of hole cutters as defined in claim 1, wherein each holecutter is attachable to an arbor including at least two drive membersfor engaging the at least two drive surfaces to rotatably drive the holecutter with the arbor.
 11. A plurality of hole cutters, wherein eachcutter is attachable to an arbor including a threaded end portion, andat least two drive members radially spaced relative to the threaded endportion and movable axially, but not rotationally, relative to thethreaded end portion between an engaged position with the drive membersengaging a respective hole cutter to rotatably drive the hole cutter,and a disengaged position with the drive members disengaged from thehole cutter, each hole cutter comprising: a blade including a blade bodydefining a respective outer diameter of less than 1¼ inches and acutting edge defined by a plurality of cutting teeth; and a base portionopposite the cutting edge and defining a threaded aperture adapted forthreadedly engaging the threaded end portion of the arbor, and at leasttwo drive surfaces radially spaced relative to the threaded aperture onsubstantially opposite sides of the threaded aperture relative to eachother and defining a distance therebetween, wherein each drive surfaceengages a respective drive member of the arbor in the engaged positionfor rotatably driving the hole cutter; wherein (i) the plurality of holecutters includes at least two hole cutters having blade bodies definingdifferent outer diameters relative to each other that are selected fromthe group consisting of: about ⅞ inch, about 1 inch, and about 1⅛inches, and (ii) the distance between the drive surfaces issubstantially the same for each of the plurality of hole cutters.
 12. Aplurality of hole cutters as defined in claim 11, wherein the pluralityof hole cutters includes three hole cutters, one hole cutter including ablade body defining an outer diameter of about ⅞ inch, another holecutter including a blade body defining an outer diameter of about 1inch, and another hole cutter including a blade body defining an outerdiameter of about 1⅛ inches.
 13. A plurality of hole cutters as definedin claim 12, further comprising a plurality of additional hole cuttershaving blade bodies defining additional different outer diametersdifferent relative to each other selected from the group consisting of:about 9/16 inch, about ⅝ inch, about 11/16 inch, about ¾ inch, about25/32 inch, about 13/16 inch, about 15/16 inch, about 1 1/16 inches, andabout 1 3/16 inches.
 14. A plurality of hole cutters as defined in claim11, wherein the outer diameter of the blade body of each hole cutter ofthe plurality of hole cutters is different than the outer diameter ofthe blade body of every other hole cutter in the plurality of holecutters.
 15. A plurality of hole cutters as defined in claim 11, whereinthe distance between the drive surfaces is within the range of about ⅜inch to about ¾ inch.
 16. A plurality of hole cutters, wherein eachcutter is attachable to an arbor including a connecting portion, and atleast two drive members radially spaced relative to the connectingportion and movable axially, but not rotationally, relative to theconnecting portion between an engaged position with the drive membersengaging a respective hole cutter to rotatably drive the hole cutter,and a disengaged position with the drive members disengaged from thehole cutter, each hole cutter comprising: first means for cutting a holehaving an outer diameter of less than 1¼ inches; second means forconnecting the first means to the connecting portion of the arbor; andat least two third means for engaging the at least two drive members ofthe arbor in the engaged position and for rotatably driving the holecutter with the arbor that are radially spaced on opposite sides of thesecond means relative to each other and defining a distancetherebetween, wherein (i) the plurality of hole cutters includes atleast two hole cutters each having first means for defining differentouter diameters relative to each other, and each outer diameter isselected from the group consisting of: about ⅞ inch, about 1 inch, andabout 1⅛ inches, and (ii) the distance between the at least two thirdmeans is substantially the same for each of the plurality of holecutters.
 17. A plurality of hole cutters as defined in claim 16, whereinthe first means is a hole cutter blade defining the respective outerdiameter, the second means is a threaded aperture, and each third meansis a drive surface located on an opposite side of the threaded aperturerelative to the other drive surface.
 18. A plurality of hole cutters asdefined in claim 16, wherein the outer diameter of the first means ofeach hole cutter of the plurality of hole cutters is different than theouter diameter of the first means of every other hole cutter in theplurality of hole cutters.